Response to steroid therapy of sclerosing cholangitis after duodenopancreatectomy due to autoimmune pancreatitis

Infiltration of peritumoural but tumour-free parenchyma with IgG4-positive plasma cells in hilar cholangiocarcinoma and pancreatic adenocarcinoma

BACKGROUND

Recently, new guidelines for diagnosing IgG4-associated cholangitis have been published devaluing the diagnostic significance of IgG4-positive plasma cells and steroid trials. We sought to evaluate the utility of IgG4-positive plasma cells in discriminating IgG4-associated cholangitis from hilar cholangiocarcinoma and autoimmune pancreatitis from pancreatic adenocarcinoma under conditions when malignancy is likely to be missed.

METHODS

Resection specimens obtained from patients with hilar cholangiocarcinoma, pancreatic adenocarcinoma or hepatocellular carcinoma were re-evaluated for IgG4-positivity. Histological analysis focussed on peritumoural but tumour-free sections. Perioperative biochemical and clinical data were reviewed.

RESULTS

Nineteen patients with hilar cholangiocarcinoma and 29 patients with pancreatic adenocarcinoma were eligible for histological re-evaluation. Six of 19 (32%) patients with hilar cholangiocarcinoma and 5 of 29 (17%) patients with pancreatic adenocarcinoma were IgG4-positive (≥20 IgG4-positive plasma cells per high power field). Patients with IgG4-positive hilar cholangiocarcinoma showed significantly higher levels of serum total bilirubin (3.6mg/dl vs. 1.8mg/dl; P<0.05) and serum alanine-aminotransferase (median 343U/l vs. 63U/l, P<0.05) compared to IgG4-negative patients with hilar cholangiocarcinoma.

CONCLUSIONS

IgG4-positive plasma cells are of limited utility especially in distinguishing hilar cholangiocarcinoma from IgG4-associated cholangitis even when combined with clinical parameters and may be misleading under conditions when malignancy is missed.

Therapeutic management and clinical outcome of autoimmune pancreatitis

BACKGROUND

Autoimmune pancreatitis, in comparison to other benign chronic pancreatic diseases, is characterized by the possibility of curing the illness with immunosuppressant drugs. The open question is whether to differentiate autoimmune pancreatitis as a primary or secondary disease based on the presence or absence of other autoimmune diseases or whether to consider autoimmune pancreatitis a clinical and pathological systemic entity, called IgG4-related sclerosing disease, since this aspect is also very important from a therapeutic point of view.

METHODS

In this paper, we reviewed the conventional therapeutic approach used to treat autoimmune pancreatitis patients and the clinical outcome related to each treatment modality. We also reviewed some aspects which are important for the correct management of autoimmune pancreatitis, such as the surgical approach, the outcome of surgically treated autoimmune pancreatitis patients, whether medical treatment is always necessary, and, finally, when medical treatment should be initiated.

CONCLUSIONS

Steroids are useful in alleviating the symptoms of the acute presentation of autoimmune pancreatitis, but some questions remain open such as the dosage of steroids in the acute phase and the duration of steroid therapy; finally, it should be assessed if other immunosuppressive non-steroidal drugs may become the first-line therapy in patients with AIP without jaundice and without atrophic pancreas.

[Bile duct involvement in autoimmune pancreatitis: classification and treatment]

Autoimmune pancreatitis is a rare disease characterized by inflammation of the pancreatic parenchyma, irregular narrowing of the pancreatic duct, periductal lymphoplasmacytic infiltration and fibrosis at histological examination, the presence of autoantibodies and hypergammaglobulinemia, as well as the possible association of cholangitis and other autoimmune diseases. There is a favorable response to steroid therapy. We report the case of a patient with autoimmune pancreatitis with bile duct involvement and peripheral eosinophilia, requiring long-term immunosuppressant treatment. The diagnosis of a diffuse form of AIP was made without direct histological evidence and based on indirect imaging, clinical and laboratory findings in an autoimmune context. The histological and imaging studies of bile duct involvement and the favourable response to steroids were additional arguments.

IgG 4-Positive Sclerosing Cholangitis Following Autoimmune Pancreatitis With Deranged CA19.9

Sclerosing cholangitis is an autoimmune condition characterized by lymphocytic infiltration within the biliary epithelium leading to multifocal stricturing of the biliary tree. Primary sclerosing cholangitis (PSC) is the most common type encountered clinically. However, a similar process may occur in conjunction with autoimmune pancreatitis (AIP), known as AIP-associated sclerosing cholangitis (AIP-SC). This subtype is associated with an elevated IgG4 level and the presence of a number of autoantibodies. AIP-SC shows good response to steroid treatment, distinguishing it clinically from PSC. The authors report a case of AIP-SC in a patient who had previously undergone a biliary bypass for AIP-induced chronic pancreatitis. The presentation of jaundice and grossly elevated tumor marker, CA19.9, raised the concern of malignancy. The uncertainty of the diagnosis was resolved when AIP-SC was confirmed on liver biopsy, with a concomitantly elevated serum IgG4 level. The disease went into remission with steroid treatment.

IgG4-related sclerosing lymphoplasmacytic pancreatitis and cholangitis mimicking carcinoma of pancreas and Klatskin tumour

BACKGROUND

Autoimmune sclerosing pancreatitis is a well-known disease entity for years, particularly recognizing the difficulty in distinguishing it from malignancy. Immunohistochemical study showed that immunoglobulin IgG4 staining was positive in plasma cells of some autoimmune pancreatitis or cholangitis. The term 'autoimmune sclerosing pancreatocholangitis' was used as it was believed that they belonged to a range of disease involving both pancreas and biliary tree. It may also be part of a systemic fibro-inflammatory disease.

PATIENTS AND METHODS

All the patients suffering from immunoglobulin G4 (IgG4)-related pancreatitis and cholangitis from May 2003 to September 2006 in Queen Elizabeth Hospital, Hong Kong were retrospectively studied.

RESULTS

A total of five patients with clinical diagnosis of IgG4-related autoimmune pancreatitis or cholangitis were analysed. All presented with jaundice or abdominal pain, mimicking carcinoma. Two patients had major resection, two patients were diagnosed by intraoperative biopsy and one was based on serum IgG4 level.

CONCLUSION

With the growing awareness of this relatively recently characterized clinical entity and its similar presentation to pancreatic carcinoma or bile duct cholangiocarcinoma, it is important for autoimmune sclerosing pancreatocholangitis to be included in the differential diagnosis of pancreaticobiliary disease. The management strategy has shown to be modified--from major resection to intraoperative biopsy and to the assay of serum IgG4 level without the necessity of histology confirmation.

Autoimmune pancreatitis

Autoimmune pancreatitis (AIP) is a benign, IgG4-related, fibroinflammatory form of chronic pancreatitis that can mimic pancreatic ductal adenocarcinoma both clinically and radiographically. Laboratory studies typically demonstrate elevated serum IgG4 levels and imaging studies reveal a diffusely or focally enlarged pancreas with associated diffuse or focal narrowing of the pancreatic duct. The pathologic features include periductal lymphoplasmacytic inflammation, obliterative phlebitis, and abundant IgG4-positive plasma cells. The treatment of choice for AIP is steroid therapy. Diagnostic criteria for AIP have been proposed that incorporate histologic, radiographic, serologic, and clinical information.

Prognosis of autoimmune pancreatitis

Autoimmune pancreatitis (AIP) is responsive to steroid therapy, but some AIP patients improve spontaneously, or only improve after biliary drainage. Pancreatic enlargement and irregular narrowing of the main pancreatic duct usually improves in almost all patients, but marked atrophy of the pancreas develops in some patients. Biliary stenosis improves to various degrees, and a biliary drainage tube can be withdrawn. Other extrapancreatic lesions, including swelling of the salivary or lacrimal glands, lymphadenopathy, and retroperitoneal fibrosis also improve with steroid therapy. Pancreatic endocrine and exocrine function is frequently impaired in AIP patients, and steroid therapy is occasionally effective for these dysfunction. Deterioration of pancreatic exocrine function is rarely detected after steroid therapy. In the literature, the recurrence rate of AIP was reported to be about 17% (range 6% to 26%). AIP patients who relapse during maintenance steroid therapy or after stopping steroid medication should be re-treated with a high-dose steroid. Although AIP is rarely associated with pancreatic stones, stones are formed in some relapsing AIP patients. The long-term prognosis for AIP is unknown. As the pancreatic exocrine and endocrine functions as well as the morphological findings are reversible after steroid therapy, the prognosis for AIP seems better than that of chronic pancreatitis, which is usually followed by exocrine and endocrine pancreatic insufficiency with disease progression. Although carcinogenesis of AIP is unknown, some AIP patients developed a malignancy during follow-up. Since AIP occurs predominantly in the elderly, clinicians should pay attention to any complicating diseases in follow-up of AIP patients. Further studies are necessary to clarify the pathogenesis as well as the long-term prognosis of AIP.

Diagnostic and treatment modalities for autoimmune pancreatitis

Since the recognition of autoimmune pancreatitis (AIP) as a clinical entity, many advances have been made in defining clinical, radiologic, histologic, and laboratory parameters to assist in a complete definition of the disease. Despite all these efforts, a preoperative diagnosis still remains a clinical challenge but is of paramount importance, as these cases have been reported to be steroid-responsive; therefore, early treatment may obviate the need for surgical resection. Although the utilization of recently proposed guidelines by the Japanese Pancreas Society and an Italian study group may further assist the clinician and prompt the initiation of steroid treatment, the response to therapy should be observed within 2 to 4 weeks and reflected in progressive resolution of the presenting radiologic and laboratory abnormalities. Should these fail to demonstrate improvement, the diagnosis of AIP should undergo re-evaluation, and consideration for surgical exploration should be made, as the patient may be harboring a malignancy. Surgical resection in the form of pylorus-preserving pancreaticoduodenectomy remains the optimal solution in the attempt to clarify the diagnosis and offer treatment with low complication rates.

Autoimmune pancreatitis: proposal of IgG4-related sclerosing disease

Autoimmune pancreatitis (AIP) is a peculiar type of pancreatitis of presumed autoimmune etiology. Many new clinical aspects of AIP have been clarified during the past 10 years, and AIP has become a distinct entity recognized worldwide. However, its precise pathogenesis or pathophysiology remains unclear. As AIP dramatically responds to steroid therapy, accurate diagnosis of AIP is necessary to avoid unnecessary surgery. Characteristic dense lymphoplasmacytic infiltration and fibrosis in the pancreas may prove to be the gold standard for diagnosis of AIP. However, since it is difficult to obtain sufficient pancreatic tissue, AIP should be diagnosed currently based on the characteristic radiological findings (irregular narrowing of the main pancreatic duct and enlargement of the pancreas) in combination with serological findings (elevation of serum gamma-globulin, IgG, or IgG4, along with the presence of autoantibodies), clinical findings (elderly male preponderance, fluctuating obstructive jaundice without pain, occasional extrapancreatic lesions, and favorable response to steroid therapy), and histopathological findings (dense infiltration of IgG4-positive plasma cells and T lymphocytes with fibrosis and obliterative phlebitis in various organs). It is apparent that elevation of serum IgG4 levels and infiltration of abundant IgG4-positive plasma cells into various organs are rather specific to AIP patients. We propose a new clinicopathological entity, "IgG4-related sclerosing disease", and suggest that AIP is a pancreatic lesion reflecting this systemic disease.